This invention relates to a self-aligning twin-wheeled caster.
Widespread acceptance has been gained, particularly for furniture items and the like articles, by self-aligning casters which comprise, in a known manner, two wheels rotatively mounted to the ends of a horizontal shaft or axle which is accommodated in a seat defined by a vertical wall, a middle wall, and a shroud or guard enclosing the wheels.
The shroud and middle wall further include a sleeve which is open at the top and carries pivotally a vertical self-alignment surface.
A frequently encountered problem with conventional self-aligning casters is that dirt, hair, threads, and other materials tend to lodge themselves between such wheels and shaft, thus unavoidably hindering the ability of the wheels to rotate and, consequently, the caster operation.
Furthermore, when applied to a chair, conventional casters are often a cause of inconvenience and potential hazard, since the chair is allowed to roll on its casters even before the user has a chance to sit on it.
For strength and appearance reasons, moreover, the trend favors casters wherein the above mentioned shroud and wall are made of metal, instead of plastics, even if obviously the cost of metal casters is higher.